Trigger finger, as the term is commonly used, refers to an abnormal condition in which flexion or extension of a finger may be momentarily obstructed, causing spasms and a snapping of the finger. In severe circumstances this condition may lock a finger in a single position or possibly effect several fingers of a person's hand. Trigger finger is most commonly experienced among middle-aged persons and, as the name implies, typically afflicts the middle finger or ring finger. This condition is commonly caused by an obstruction which prevents the flexor tendon from moving freely within the protective sheath. Such an obstruction may be caused by the formation of a nodule on the flexor tendon or by the swelling of the flexor tendon itself; the nodule or swelling of the tendon restricts the movement of the tendon within the sheath thereby causing the spastic or uncontrolled movement.
Today this problem is typically treated using conventional surgical techniques and instruments in an open operative procedure. An incision is made in the palm of the hand adjacent the distal crease in the palm. The flexor sheath is then explored through the incision and a cutting instrument is inserted through the incision in order to cut a portion of the sheath. Cutting a portion of the sheath over the flexor tendon relieves the constriction, "releasing" the tendon, and eliminating the spastic movement. However, when cutting the sheath it is important not to disturb or cut the neurovascular bundles located near the tendon. The incisions are subsequently sewn shut and allowed to heal. However, even after the hand has fully healed from such an operative procedure the person is typically left with an unsightly scar. In addition, the use of such conventional techniques often requires that the procedure be performed in an operating room and adherence to strict protocols which result in the expenditure of considerable time and money.
Therefore, there exists a need for a percutaneous method of treating trigger finger which does not require significant open incisions. Moreover, there is a need for a percutaneous method of treating trigger finger which allows the procedure to be performed as an office procedure. There likewise exists a need for a method and apparatus which allow medical professionals to quickly and safely perform such a procedure without risk to the numerous neurovascular bundles located throughout the hand.